No.
It was just bad gameplay trying to get as little XP and skip parts of the game just to get a overpowered boost that wasn't even intended to be used that way.
I'm all for min-maxing but people only find out about these books when it's already too late forcing those min-maxers to either restart or play with the consequences (any real min-maxer can't choose the latter)
They should however had made it 2 or 4 books. So both characters in coop can get one, or you can still choose to create a more hybrid character that uses all 2/4 books.
There's plenty of replayability in this game and it's already easy enough once you min-max.
The book change was a good move.
